Bin Laden was intelligent, well-informed, and low key. The people around him treated him with great deference, calling him 'sheikh,' a term of respect.

The special reverence that al Qaeda had for Sheikh Rahman was underlined by a two-hour propaganda videotape that the group's media division released in the spring of 2001, when the 9/11 attacks were in their final planning phase.

I've interviewed multiple people who know bin Laden... who tend to have a universal picture of what he's like, which is: modest, retiring, unassuming, kind of thoughtful - lots of things that don't fit with a mass murderer, which he is as well.

An intelligence officer and historian, Rayburn published a 2014 book, 'Iraq After America,' which is a must-read for anyone who wants to understand how Iraq descended into chaos in the years after the American troop withdrawal at the end of 2011.

Will there be a political backlash against British Prime Minister Theresa May, whose ruling Conservative Party is traditionally seen as 'stronger' on terrorism than its main rival, the Labour Party?